Across the great divide: Proteomics becoming an essential tool for animal and veterinary sciences

Comprehensive analysis of blood proteome response to necrotic enteritis in broiler chicken

Necrotic enteritis (NE) in broiler chickens is caused by the overgrowth of toxin-producing strains of Clostridium (C.) perfringens. This study aims to analyze the blood proteome of broiler chickens affected by NE, providing insights into the host's response to the infection. Using MS/MS-based proteomics, blood plasma samples from broilers with necrotic lesions of different severity were analyzed and compared to healthy controls. A total of 412 proteins were identified, with 63 showing significant differences; for 25 of those correlation with disease severity was observed. Functional analysis revealed that proteins affected by NE were predominantly associated with the immune and signaling processes and extracellular matrix (ECM) structures. Notably, regulated proteins were significantly involved in bioprocesses related to complement activation, acute phase reaction, proteolysis and humoral immune response. The proteomics findings suggest that the changes in plasma proteins in response to NE are driven by the host's intensified efforts to counteract the infection, demonstrating a.o. activation of ECM-degrading proteases (MMP2, TIMP2), acute phase response (HPS5, CP, EXFABP, TF, VNN) and notable reduction in basement membrane (BM) and ECM-related peptides (PLOD2, POSTN, COL1A1/2, HSPG2, NID2) detected in the blood of NE-affected birds. Moreover, the findings underscore a coordinated effort of the host to mitigate the C. perfringens infection via activating immune (a.o., C3, CFH, MASP2, MBL2) and acute phase (CP, ORM, TF, ExFAB) related proteins. This study provides a deeper understanding of the host-pathogen interactions and identifies potential biomarkers and targets for therapeutic intervention. Data are available via ProteomeXchange with identifier PXD054172.

ITRAQ-based quantitative proteomics analysis of forest musk deer with pneumonia

Pneumonia can seriously threaten the life of forest musk deer (FMD, an endangered species). To gain a comprehensive understanding of pneumonia pathogenesis in FMD, iTRAQ-based proteomics analysis was performed in diseased (Pne group) lung tissues of FMD that died of pneumonia and normal lung tissues (Ctrl group) of FMD that died from fighting against each other. Results showed that 355 proteins were differentially expressed (fold change ≥ 1.2 and adjusted P-value < 0.05) in Pne vs. Ctrl. GO/KEGG annotation and enrichment analyses showed that dysregulated proteins might play vital roles in bacterial infection and immunity. Given the close association between bacterial infection and pneumonia, 32 dysregulated proteins related to Staphylococcus aureus infection, bacterial invasion of epithelial cells, and pathogenic Escherichia coli infection were screened out. Among these 32 proteins, 13 proteins were mapped to the bovine genome. Given the close phylogenetic relationships of FMD and bovine, the protein-protein interaction networks of the above-mentioned 13 proteins were constructed by the String database. Based on the node degree analysis, 5 potential key proteins related to pneumonia-related bacterial infection in FMD were filtered out. Moreover, 85 dysregulated proteins related to the immune system process were identified given the tight connection between immune dysregulation and pneumonia pathogenesis. Additionally, 12 proteins that might function as crucial players in pneumonia-related immune response in FMD were screened out using the same experimental strategies described above. In conclusion, some vital proteins, biological processes, and pathways in pneumonia development were identified in FMD.